In general, an audio-visual (AV) system is mounted on a crash pad installed throughout an interior of a vehicle in order to secure a driver's convenience.
A monitor, which can display AV system related information or display map information with introduction of a navigation system so as for the driver to easily recognize required information visually, is mounted integrally with an AV system.
Meanwhile, in recent years, an AV system, which enables the driver to watch broadcasting through a public TV network or a satellite or view DVD movies even in motion, has been mounted.
Therefore, a function of an AV apparatus installed on the crash pad of the vehicle, such as watching TV or a movie as well as listening to music, has been more diversified and complicated.
As a result, multiple operating buttons to drive the aforementioned various functions are provided on a front panel of the AV apparatus, and a lighting button, which can be lit by an LED installed on a printed circuit board (PCB), is provided so as for the driver to easily recognize the buttons even at night.
The lighting button is generally configured to include a button unit and a light guide (reflector) that is placed on the circumference of the button unit and radiate light generated from a light source unit to the outside.
When the button unit is a push type, the button unit and the light guide are spaced apart from each other in order to prevent interference caused by a contact between the light guide placed on the circumference of the button unit and the button unit when the button unit is pressed.
Accordingly, the light radiated from the light source unit leaks to the outside through a spaced clearance between the light guide and the button unit, and as a result, an effect of a lighting cannot be clearly expressed and the lighting becomes nonuniform.